Most unnecessary caliber ever made

This is a discussion on Most unnecessary caliber ever made within the Defensive Ammunition & Ballistics forums, part of the Defensive Carry Discussions category; I was thinking about the hundreds upon hundreds of calibers/cartridges of ammo that have been made throughout history. Some have been legends and we all ...

Most unnecessary caliber ever made

I was thinking about the hundreds upon hundreds of calibers/cartridges of ammo that have been made throughout history. Some have been legends and we all know them (.45ACP/LC, 9mm, .357, 30-30, 7.62x39, etc.) but there have been some calibers that have been just flat out busts or never caught on with the public or even worse just sucked and had terrible performance in general. So what do you guys feel is the most pointless or useless caliber ever made? It can be pistol or rifle. The answers should be interesting for sure! Here is my pick

9mm Federal Rimmed or 45 GAP.

9mm Federal was kind of a good idea to have a 9mm cartridge that would function normally without moon clips or other means in revolvers. But most revolver shooters weren't interested in it, Charter Arms was the only company making revolvers for it (I think, correct me if I'm wrong) and the cartridges would fit right into a 38 S&W chamber and produce very unpleasant kabooms.

* This is said in sarcasm, actually. I'm sure the .600 NE would work just dandy on a 15ft African elephant, or similar, though I'd hate to give odds at being capable of making a follow-up shot with a broken shoulder.

* This is said in sarcasm, actually. I'm sure the .600 NE would work just dandy on a 15ft African elephant, or similar, though I'd hate to give odds at being capable of making a follow-up shot with a broken shoulder.

Shoulder?

SHOULDER?

Pretty sure you're required to turn in your man card if you shoot the .600 NE in anything but a revolver:

I get the concept of the .45 GAP, shorter round to allow a smaller grip for the primarily female small hands in LE, yet retaining the potential of the .45 ACP. Fact is, the demand never materialized, although the FHP carries it.